BACKGROUND: Since THMs were first discovered in drinking water in the early 1970s, DBP issues have become a major regulatory driving force in the United States. To date, more than 600 DBPs have been identified in drinking waters; however, only 11 DBPs (4 trihalomethanes [THMs], 5 haloacetic acids [HAAs], bromate and chlorite) are currently regulated. Available toxicological data indicates that ...

A simple, precise, sensitive and accurate method was developed for rapid determination of trace quantities of iodate. The method is based on the accelerating effect of iodate on the reaction of bromate and chloride acid in the presence of hydrazine in acidic media. The decolorization of Methyl Orange with the reaction products was used to monitor the reaction spectrophotometrically at 525 nm. I...

Because it is more stable than iodide, most health authorities preferentially recommend iodate as an additive to salt for correcting iodine deficiency. Even though this results in a low exposure of at most 1,700 microg/d, doubts have recently been raised whether the safety of iodate has been adequately documented. In humans and rats, oral bioavailability of iodine from iodate is virtually equiv...

A method for rapid and accurate determination of trace quantities of SbIII was developed based on its inhibitory effect on the decolorizing reaction of methyl orange in the presence of bromate and bromide ions in acidic media. Decolorization of methyl orange by the reaction products was used to monitor the reaction spectrophotometrically at 525 nm. The method allows determination of antimony in...

A luminescent multilayer film has been fabricated from the polyoxometalate anion α[PMo12O40]3− (α-PMo12) and the cation Fuchsin Basic (FB) through an electrostatic layer-by-layer (LbL) self-assembly method and characterized by UV/Vis spectra, atomic force microscopy and X-ray photoelectron spectra. The fluorescence properties of the LbL film have also been investigated. Cyclic voltammetry measu...

A kinetic spectrophotometric method for measuring thiocyanate is described. The proposed method is based on the inhibitory effect of thiocyanate on the oxidation of Methyl Red by bromate in the presence of nitrite, which was monitored at 520 nm. The variables affecting the rate of the reaction were investigated and the optimum conditions were established. Thiocyanate can be measured in the rang...

An advanced stopped-in-loop flow analysis (SILFA) is proposed for the catalytic determinations of vanadium and iron. The chemistry relies on a vanadium- or iron-catalyzed oxidative reaction of p-anisidine by bromate or hydrogen peroxide in the presence of an activator (Tiron or 1,10-phenanthlorine) to form a red dye (510 nm). Reagents for the vanadium- or iron-catalyzed reaction are well mixed ...

A simple, economical, precise and fast visible spectrophotometric method has been developed for the determination of Azathioprine in tablet dosage form. Developed method is based on the formation of extractable colored complex of drug with colouring agent Indigo Carmine and Methyl orange. A wavelength maximum was found to be 683.7 nm and 566 nm. The concentration range of 15-50 μg mL-1 with of ...